Process for the production of carbon-covered metal sheets for dynamo-brushes.



\ and the Lille, ol' \i'hieh the lollmving' ii/zin (X- T @FFHJE.

.lOllANNlCH l l-illilillllll Il-IIEii RINlrSliORFF, (ll ESSEN-ON-THF-RUHR, GERMANY.

Application filed July 14, 1908.

Specification of Letters Patent.

Patented June 1, 1909.

Serial No. MSASQ.

To all 1.0120121 it 'illl'll/ i-onwrlz: l Be il known lhnl l, JOHAXYES FRHCURHH li-z'rnn liixusnonri, n subletoi the l'iing ol' Prussia, and u l'(-;lililil oi lironprinuuil Astrnsse, oi lCsscn-on-ilic-lluhr, in (he iv-l mun Empire, lime invented it new nud use i'ul Process for the Production oi ('nrhon (ovcred Metal Sheers l'or li unino-Bnushes net specificati n.

This invention relates to 2t ljlf'l during the known will i, prei er v l'orm oi' gruphilc. eorm'ed sheer i' which are used in dyngimo brushes or n the diuphrugms oi microphones. llereto'l'oro ii hus hcen custonnu to cover the tmn sheets oi inclin-l vith carbon and then lo prepare the sheet covered in this wiry l'or dynnmo brushes. Such brushes however presiuit the dismmntnge that the ezirizon layers adhere poorly to the sheet. The loose adhesion be tween the carbon and the metal causes a bird electric conduction and damaging o the collectors. When brushes prepared in this way we subjected to -:i higher pressure such for example us takes place when lormli'ig the brushes out of ii bundle oi sepzirute plates, the pressure causes the carbon to be sealed oil or thinned in pzi'rts so that the layer does not. preserve the necessary evenness.

According to the present invention the pulverized carbon prcl'ernbly graphite mny simply be applied in form of u pnste which i l u pro ulii nniy be smeared over the metal sheets.

\ihen the carbon preferably graphite has been applied to the metal sheets zind IS in the proper dry condition, tho sheets are subjected to high pressure, for example 100 to 1500 kg. per sq. cm. This is eflected by means of rollers or hydraulic pressure. When thus prepared the carbon adheres firmly to the sheets which now are ready to to be worked up into dynamo brushes or mcinbrunes of microphones. Small sheets, coated as described may be directly formed into brushes and membranes. Carbon routed sheets thus prepared may be subjected lo pressure during the nuin'ufacture of the dynamo brushes without showing any unevenness nor does any sealing of the carbon oecu-r.

1 claim as my invention:

1. The 'n-oeess of producing carbon covered meta sheets consisting in smearing a :nrbon paste on the surfaces of sziid metal sheets und sulnectmg them tohigh )ressure.

2, The process of'producing our on covered metal sheets consisting in-smea-ring u am subjecting them to hydraulic pressure. in witness whereof I have hereuntoset my hand in the presence of two witnesses.

' JOliANJES Filllllllllllll l l'lER ltlNGSllOll-Fl". Witnesses 4 PETER Lmsnn, WIL'HELM Fmsonu.

graphite paste on the surfaces of the sheets 

